private static Expression MakeWhereMethod(Expression context, Expression argContext, string methodName, Expression[] args)
{
ExpectArgsCount(1, args, methodName);
var predicate = args.First();
ExpectArgTypeToBe(predicate.Type, typeof(bool), methodName);
var lambda = Expression.Lambda(predicate, argContext as ParameterExpression);
return ExpressionUtil.MakeExpressionCall(new []{typeof(Queryable), typeof(Enumerable)}, "Where", new Type[] {argContext.Type}, context, lambda);
}
private static Expression MakeOrderByMethod(Expression context, Expression argContext, string methodName, Expression[] args)
{
ExpectArgsCount(1, args, methodName);
var column = args.First();
var lambda = Expression.Lambda(column, argContext as ParameterExpression);
return ExpressionUtil.MakeExpressionCall(new []{typeof(Queryable), typeof(Enumerable)}, "OrderBy", new Type[] {argContext.Type, column.Type}, context, lambda);
}
private static Expression MakeTakeMethod(Expression context, Expression argContext, string methodName, Expression[] args)
{
ExpectArgsCount(1, args, methodName);
var amount = args.First();
ExpectArgTypeToBe(amount.Type, typeof(int), methodName);
return ExpressionUtil.MakeExpressionCall(new []{typeof(Queryable), typeof(Enumerable)}, "Take", new Type[] {argContext.Type}, context, amount);
}
private static Expression MakeOptionalFilterArgumentCall(Expression context, Expression argContext, string methodName, Expression[] args, string actualMethodName)
{
ExpectArgsCountBetween(0, 1, args, methodName);
var allArgs = new List<Expression> { context };
if (args.Count() == 1) {
var predicate = args.First();
ExpectArgTypeToBe(predicate.Type, typeof(bool), methodName);
allArgs.Add(Expression.Lambda(predicate, argContext as ParameterExpression));
}
return ExpressionUtil.MakeExpressionCall(new []{typeof(Queryable), typeof(Enumerable)}, actualMethodName, new Type[] {argContext.Type}, allArgs.ToArray());
}